Thermal insulation for buildings and other structures is available in the form of mats, batts, blankets and loose fill. Mats, batts and blankets are flexible products containing randomly-oriented fibers bound together with a binder, and are generally prefabricated before being brought to a construction site and installed. In contrast, loose fill thermal insulation includes a large number of discrete fibers, flakes, powders, granules and/or nodules of various materials.
Efforts have been made to reduce the thermal conductivity of insulation. See for example U.S. Pat. App. No. 2005/0025952, directed to heat resistant insulation composites and methods of preparing them; U.S. Pat. App. No. 2005/0079352, directed to expandable microspheres for foam insulation and methods for preparing same; U.S. Pat. No. 6,864,297, directed to composite foam materials made from polymer microspheres reinforced with long fibers; U.S. Pat. No. 6,638,984, directed to microcellular foams, their method of production and uses thereof; U.S. Pat. No. 5,418,257, directed to modified low-density polyurethane foam bodies; U.S. Patent Application Nos. 2003/0087576 and 2003/0040239, directed to infrared radiation absorbing and scattering material dispersed on insulation material